It is the long-term goal of this research effort to gain further insight into binocular eye movement control mechanisms. We propose to make biophysical and behavioral measurements on normal subjects and on strabismus patients before, during and at intervals following surgery. Specifically we plan to identify innervation pattern imbalances and will determine the mechanical load characteristics of the muscles and globe restraining tissues. By this means we will evaluate the motor, mechanical and control elements of ocular rotation. The data obtained will be used to formulate a general clinical model of oculomotion as well as specific diagnostic models of individual strabismus patients quantifying pathophysiological changes. We propose to develop these techniques to provide a quantitative basis for understanding diagnosis and treatment of oculomotor disorders.